|Elevation||7 m (23 ft)|
|Time zone||IST (UTC+5:30)|
The town is a main hub for the nearby villages. Many of the population are farmers. This is the native place of Tamil film director Kailasam Balachander, lyricist Piraisoodan and cinematographer R. Mathi. Nannilam is located 30 km west of Karaikal and 30 km east of Kumbakonam. The people mainly depend on agriculture, almost 70% of the population are employed in agriculture,
Most of the villages developed along the river banks. The Thriumalai rajan river (branch of Cauvery) flows in Nannilam taluk. On the bank of Tirumalarajanar River, One Sai Baba temple was established in local Siddhi Vinayak temple at Jaganthapuram.
Nannilam and the surrounding area is home to many temples, including Madhuvaneshwarar Temple, an old Shiva temple which is located center of the town. The Saraswathy Amman temple (the only temple for Saraswathy amman in South India) is located at koothanur (near Poonth thootam), 8 km from Nannilam. This place was known as “Ambalpuri”, about 1000 years ago at which time the Sri Lalithambikai Temple in Thirumeeyachur (Constructed by Kunthavai Naachiyaar, Sister of Rajarajan Chola) was built, an awe-inspiring example of Chola architecture.
Anjenayur kovil, near Nemmeli is a temple to Lord Anjenaya Studys Ramayan.
- Sri Saraswathy Amman temple, Koothanur (near Poonthottam)
- Sri Somanatha Swamy Temple, Achuthamangalam
- Sri Maha Mariamman Temple, Achuthamangalam
- Sri Veeramaga Kaliyamman Temple, Sakkara Kothangudi - 609503
- Mudikondan Sri Kothandaramar temple, Sri prasana venkatesa permual temple,sri kaliamman temple
- Siddhi Vinayak & Saibaba temple, Jaganathapuram (Near Nemmeli), Just 6 km from Nannilam. To reach this Saibaba temple from Nannilm, Nallumangudi, Kammangudi and to Jaganthapuram
- 1000-year-old Sri Lalithambikai Temple in Thirumeeyachur -Peralam (Constructed by Kunthavai Naachiyaar, Sister of Rajarajan Chola)
- Sri Svarnakaliamman Temple
- Sri Veeramaakaaliyamman Temple
- Sandhuveli Mariamman Kovil
- Panchamuga Anjaneya Temple at Vadagudi
- Sri Pasupathiswarar kovil, Thirukondeeswarm
- SriVanchiyam Temple
- Kaliamman kovil & old Siva temple, Kammangudi(Near Nannilam)
- Mariamman kovil, thengudi(Near Nannilam)
- Anjenayur kovil Near Nemmeli (Siginifigance of this temple is Lord Anjenaya Studys Ramayan)
- Saibaba Temple in Moolangudi near nannilam.
- அருள்மிகு பெத்தனார் பாட்டை ஐயனார் சுவாமி கோவில் ....மனுவை.
- Sri Gnambigai amman temple,Thirumeignanam-609403
- sri Bathrakaliyamman temple,Thirumeignanam-609403
- Sri Mariyamman temple,Thirumeignanam-609403
According to the 2001 Indian census, Nannilam then had a population of 9880. Males constitute 50% of the population and females 50%. Nannilam has an average literacy rate of 75%, higher than the national average of 59.5%: male literacy is 81%, and female literacy is 68%. 10% of the population is under 6 years of age.
The Population density (people per km2)of Nannilam assembly constituency is just 60 against India’s 393.83 in 2010 (Just 15% of average India's Population density) .
- Ezhumalaiyan polytechnic at Kollumangudi
- Arooran Polytechnic at Sorakudi
- Central University at Vandampalai, Tiruvarur District
- Tamil Nadu ITI at Vandampalai.
- Merit Higher Secondary School at Senthamangalam, Tiruvarur District
- Sankara Matriculation (CBSE Syllabus) School at Peralam
- Government Higher Secondary School and High School at Nannilam, Peralam, Poonthottam, Mudikondan, Srivanjiam
- George Higher Secondary School at Vishnupuram, Eravanchery, Nannilam Taluk
- Panchayat Union School at Kammangudi, Vadagudi (post), Nannilam Taluk
- Panchayat Union Primary School at Moolangudi,Anaikuppam(post),Nannilam Taluk
- Maha jana sabha govt aided elementary school established by Somu vadhyaar, vadhyaar Venugopala ayyar.
- Thangam Nadunilai Palli Nallamagudi.
- Panchayat Union Elementary School,thirumaignanam-609403
- "Census of India 2001: Data from the 2001 Census, including cities, villages and towns (Provisional)". Census Commission of India. Archived from the original on 2004-06-16. Retrieved 2008-11-01.
- "List of Parliamentary and Assembly Constituencies" (PDF). Tamil Nadu. Election Commission of India. Retrieved 2008-10-12.